xref: /openbmc/linux/drivers/rtc/rtc-starfire.c (revision 1fa6ac37)
1 /* rtc-starfire.c: Starfire platform RTC driver.
2  *
3  * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/rtc.h>
10 #include <linux/platform_device.h>
11 
12 #include <asm/oplib.h>
13 
14 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
15 MODULE_DESCRIPTION("Starfire RTC driver");
16 MODULE_LICENSE("GPL");
17 
18 static u32 starfire_get_time(void)
19 {
20 	static char obp_gettod[32];
21 	static u32 unix_tod;
22 
23 	sprintf(obp_gettod, "h# %08x unix-gettod",
24 		(unsigned int) (long) &unix_tod);
25 	prom_feval(obp_gettod);
26 
27 	return unix_tod;
28 }
29 
30 static int starfire_read_time(struct device *dev, struct rtc_time *tm)
31 {
32 	rtc_time_to_tm(starfire_get_time(), tm);
33 	return rtc_valid_tm(tm);
34 }
35 
36 static const struct rtc_class_ops starfire_rtc_ops = {
37 	.read_time	= starfire_read_time,
38 };
39 
40 static int __init starfire_rtc_probe(struct platform_device *pdev)
41 {
42 	struct rtc_device *rtc = rtc_device_register("starfire", &pdev->dev,
43 				     &starfire_rtc_ops, THIS_MODULE);
44 	if (IS_ERR(rtc))
45 		return PTR_ERR(rtc);
46 
47 	platform_set_drvdata(pdev, rtc);
48 
49 	return 0;
50 }
51 
52 static int __exit starfire_rtc_remove(struct platform_device *pdev)
53 {
54 	struct rtc_device *rtc = platform_get_drvdata(pdev);
55 
56 	rtc_device_unregister(rtc);
57 
58 	return 0;
59 }
60 
61 static struct platform_driver starfire_rtc_driver = {
62 	.driver		= {
63 		.name	= "rtc-starfire",
64 		.owner	= THIS_MODULE,
65 	},
66 	.remove		= __exit_p(starfire_rtc_remove),
67 };
68 
69 static int __init starfire_rtc_init(void)
70 {
71 	return platform_driver_probe(&starfire_rtc_driver, starfire_rtc_probe);
72 }
73 
74 static void __exit starfire_rtc_exit(void)
75 {
76 	platform_driver_unregister(&starfire_rtc_driver);
77 }
78 
79 module_init(starfire_rtc_init);
80 module_exit(starfire_rtc_exit);
81